Ftpplicatlon



'L. F. FULLER.

RADiOTELEGRAPHY. APPLICATION FILED MAY 15, me.

Patented June 10, 1919 WITNESSES:

IN VEN TOR. L. F. FULLER M ATTORNEYS.

. ATS

LEQhIi-HELD E, FULLER, Q1 SAN FRANCISCO, CALIFORNIA, ASSIGNOR T0TELEGRAPH C(BMPANY, OF SAN FRANCISGO, GALIFQEIHA, A CGEPORATIQH-RADIOTELEGRAJPHY.

Specification of Letters Patent.

Patented June re,

Application file-cl May 15, 1916. Serial N'o. QT/$87.,

12 9 all whom c't may concern:

Be it mown that l, LEONARD F. FoLLnn,

An object of the invention is to provide a simple and efficientsignaling system for railiotelegraphy transmission stations,

The invention possesses other advanta- "ous features, some of which,With the fore .oing, will he set forth at length in the "ollriWingdescription Where I shall outline in full that form of the inventionwhich I have selected for illustration in the drawin? acconmarvin andformin art of the i s I r. e

In said drawing I present specification. have shown one specific form ofmy inventron, but it is to he understood that I do not imit myself tothe form shown.

Referring to said; drawing:

The figure is a diagrammatic representation of a radiotelegraphtransmission sys- With one form of the apparatus or"- my inventionarranged therein. The system in cludes suitable source of oscillations,preferahly continuous oscillations, such as the are 2 which inclosecl ina hydrogen atmosphere. Current is furnished to the arc loy directcurrent generator 3, betweenwhich i the are or arranged. suitablechoirsoi the arc grounded by nici the other side is coniating conductoror antenna irough the conductor f? and the variable ouctance fl.Signaling has heretofore 1y heen :tiectecl by varying the Wave h of theradiated wave, by short circursing a portion of the inductance, hut inhigh pews-roll stations the current in the short circuit is large,makingsignaling clif- In accordance with the present invention provide asecond oscillatory circuit containing an inductance. 9 and a capacity-12 and an energy consuming; element which is controllable to vary thelosses occurring therein, which cir hit is shunted around the source ofoscillations are 2. When an arc is shunted by two dissimilar oscillatoryt circuits, it will oscillate upon one circuit or the other, but willnot oscillate upon both. at the same time and will oscillate upon thecircuit upon Which it is easiest to oscillate,

to the total neglect of the other. By vary- 36 ing the losses in theshunt circuit, this cuit is chosen or neglected by the hscillations andconsequently the radiating circuit is either neglected or chosen. I

The energy consuming element comprises 6 3 a core 14- formed ofstih'iron laminaticns, which are so chosen as to provide a largehysteresis loss, especially at high quencies. A 'coil 15, formingpartthe shunt oscillatory circuit, is wound on a '7 portion of the core andthe current in the coil produces a flux in the core, Which a loss ofenergy due to hysteresis. By re ducing the hysteresis, the losses areClHCOfl, so that the oscillations will 7' the shunt circuit to theneglect of the ing circuit. This loss may he reducer subjecting the ironcore to a M. M. duced by a direct current coil 16, wh Wound on. aportion of the core and or in circuit With the battery 17, A arranged inthe battery circuit p" means for opening and closing such Chokecoils 19are preferably arrani tween the battery and the coil 16 to pi i the high"frequency current generated in coil from passing into the battery, or omeans to accomplish this result may he us The size of the coil andbattery are pr erahly such that when the key isclosed, the core issaturated, thereby reducing the hys teresis and hence the losses in theshunt circuit. Due to the losses, the core becomes heated and in cicle]? to dissipate the host, the core is immersed in an oil bath 21through which pipes 22 carrying cooling Water pass. i Signaling isaccomplished loy opening and closing the key 18; closing the D. circuitserving to recluce the hysteresis snail hence the losses in the shuntcircuit, there-- by causing the arc to oscillate upon that circuit tothe neglect of the radiating circult and opening the 3. circuit,causing;

and increase in the losses in the shunt circuit and thereby causing thearc to oscillate in the radiating circuit,

-1 claim:

In a radiotelegraphy cransmission system, a source of oscillations, (Lmdiann ciircnit connected to said source, an oscilla '0 cuit shuntedaround said source, the L circuits hearing such relation each other thatthe oscillations will prefer one circuit to the total neglect oftheother, means v ncomes in the oscillatory circuit for producinghysteresis losses and means for varying said losses to cause theoscillations to prefer the other circuit.

In testimony whereof, I have hereunto set my hand at San Francisco,California, this 2nd day of May, 1916.

LEONARD r. FULL R.

I In presence of- H. G. Pnos'r.

